saxon:highest
Finds the items having the highest value for some expression.
highest($input as item(*)) ➔ item()*
Arguments | |||
| $input | item(*) | The input sequence |
Result | item()* | ||
highest($input as item(*), $key as function(*)) ➔ item()*
Arguments | |||
| $input | item(*) | The input sequence |
| $key | function(*) | Function to compute the sort key |
Result | item()* | ||
Namespace
http://saxon.sf.net/
Notes on the Saxon implementation
Available since before Saxon 8.0. Changed in Saxon 9.5 to take a function rather than an expression as the second argument.
Details
This function returns the item or items from the input sequence that have the highest
value for the function $key. If the second argument is omitted, it defaults
to the function fn:data#1, that is, it atomizes the item from the input
sequence.
The $key function is evaluated for each item in $input in
turn, with that item supplied as the parameter to the function. Any NaN values are
ignored. If the input sequence is empty, the result is an empty sequence. If several
items have the highest value, the result sequence contains them all.
Strings are compared using the default collation from the static context.
Example: saxon:highest(sale, function($x){$x/@price * $x/@qty}) will
evaluate price times quantity for each child <sale> element, and
return the element or elements for which this has the highest value.